The composite term Gojirasaurus is derived from the name of the giant Japanese movie monster "Gojira" (Godzilla) and the Greek word "sauros" (σαυρος) meaning "lizard"; thus, "Godzilla lizard". In addition, a theropod dinosaur with the name Godzillasaurus exists in the Heisei era of Godzilla films, and in that continuity is explained to be the unmutated form of Godzilla. "Gojira" was selected as a reference to the great size of this theropod, which exceeded that of its Triassic counterparts. The specific name quayi, is a reference to Quay County, New Mexico, where the holotype specimen was discovered. Gojirasaurus was described and named by Kenneth Carpenter in 1997 and the type species is Gojirasaurus quayi.